News

–––––▼––––– 2025 –––––▼–––––

2025-12-07: New article published in Atmospheric Measurement Techniques: Sensitivity of tunable infrared laser spectroscopic measurements of ∆’¹⁷O in CO₂ to analytical conditions. In this paper, we examined how to improve the accuracy of a laser-based method for measuring oxygen isotopes in CO₂, focusing on the rare mass-17 isotope. By testing instruments in two labs, we identified ways to make the results more reliable. Our findings provide practical guidance and support wider use of this method in environmental studies. Download the PDF. Read the article online.

–––––▼––––– 2024 –––––▼–––––

2024-07-31: New article published in Geochemical Perspectives Letters: Correcting for vital effects in coral carbonate using triple oxygen isotopes. In this paper, we demonstrate how triple oxygen isotope measurements can be used to accurately determine growth temperatures from kinetically biased biogenic carbonates. Additionally, we show that triple oxygen isotope data provide insights into the processes responsible for vital effects. Download the PDF. Read the article online. Read the press release.

2024-03-28: New article published in Chemical Geology: Triple oxygen isotope systematics of CO₂ hydroxylation. In this paper, we quantified the ¹⁷O/¹⁶O and ¹⁸O/¹⁶O kinetic isotope fractionation factors related to CO₂ absorption using precipitation experiments and theoretical modelling. Download the PDF. Read the article online.

2024-01-13: New article published in Precambrian Research: Aspects of the biological carbon cycle in a ca. 3.42-billion-year-old marine ecosystem. The well-preserved carbonaceous matter from the Buck Reef Chert offers insights into diverse microbial metabolisms, suggesting the existence of an advanced biological carbon cycle in the early Archean. This study was led by Manuel Reinhardt. Download the PDF. Read a news report. Read the article online.

–––––▼––––– 2023 –––––▼–––––

2023-10-17: New article published in Geochemistry, Geophysics, Geosystems: A dual inlet system for laser spectroscopy of triple oxygen isotopes in carbonate-derived and air CO₂. Two years of work finally came to fruition! This paper outlines our custom-built dual-inlet system coupled with an Aerodyne TILDAS laser spectrometer, which we use for routine triple oxygen isotope analyses of CO₂. Download the PDF. Read the article online.

2023-08-24: Results from an in-progress study Triple oxygen isotope measurements of air CO₂ around Göttingen will be presented at the GeoBerlin conference on 4 September 2023. Read the abstract here.

2023-08-23: New article published in Geochimica et Cosmochimica Acta: Isotopic disequilibrium in brachiopods disentangled with dual clumped isotope thermometry. The paper discusses how to acquire accurate paleotemperature information from brachiopods using combined ∆₄₇ and ∆₄₈ measurements. Read the article online.

–––––▼––––– 2022 –––––▼–––––

2022-08-11: Results from an in-progress study Isotope fractionation mechanisms involved in carbonate formation revealed by high-precision triple oxygen isotope analyses will be presented at the GeoMinKöln (Cologne, Germany) and the 8^th Clumped Isotope Workshop (Jerusalem, Israel) conferences in September 2022. Read the abstract here (PDF, 2 Mb).

–––––▼––––– 2021 –––––▼–––––

2021-11-16: New article published in ACS Earth and Space Chemistry: Kinetic oxygen isotope fractionation between water and aqueous OH^– during hydroxylation of CO₂. We observe a 24‰ offset between the experimental and theoretical-equilbrium isotope fractionation values. We argue that this offset derives from kinetic isotope effects related to the preferential reaction of isotopically light OH^– during CO_2(aq) hydroxylation. Read the article here.

2021-08-01: As my 2-year postdoc is over, I am moving from the University of Cologne to the University of Göttingen, where I will continue my work on clumped and triple oxygen analyses of carbonates with Prof. Andreas Pack. For my updated contact information, please refer to the Contact page.

2021-06-04: New article published in Paleoceanography and Paleoclimatology: Warm high-elevation mid-latitudes during the Miocene Climatic Optimum: Paleosol clumped isotope temperatures from the Northern Rocky Mountains, USA. Palaeosol carbonate ∆₄₇ records from Montana and Idaho suggest stable (21±2 °C) continental temperatures over the Miocene Climatic Optimum (ca. 17–15 million years ago). Read the open access article here.

2021-06-02: New article published in Geophysical Research Letters: Devils Hole calcite was precipitated at ±1 °C stable aquifer temperatures during the last half million years. In this study, we investigated the Devils Hole caves that provide a reference oxygen isotope time series for North America. Dual clumped isotope thermometry (∆₄₇ and ∆₄₈) reveals that groundwater temperature did not change significantly in the last half-million years. Variations in the oxygen isotope composition of the deposited carbonates solely reflect variations in the oxygen isotope composition of the groundwater. Read the open access article here.

2021-05-13: Results from an in-progress study An experimental constraint on the oxygen isotope fractionation (¹⁸O/¹⁶O) between water and aqueous hydroxide ion will be presented at the Goldschmidt online conference on 7 July 2021. Read the abstract here.

2021-04-13: New article published in Geochemistry, Geophysics, Geosystems: InterCarb: A community effort to improve inter‐laboratory standardization of the carbonate clumped isotope thermometer using carbonate standards. This community effort, led by Stefano Bernasconi and involving 22 laboratories, provides consensus ∆₄₇ values for carbonate standards and describes best practices for carbonate-based standardisation. Read the open access article here. Read the research spotlight here.

2021-03-09: The article Dual clumped isotope thermometry resolves kinetic biases in carbonate formation temperatures is featured in Nature Communications’ Editor Highlights.

2021-03-03: Results from an in-progress study An experimental constraint on the oxygen isotope fractionation (¹⁸O/¹⁶O) between water and aqueous hydroxide ion will be presented at the EGU21 conference. Read the abstract here.

–––––▼––––– 2020 –––––▼–––––

2020-12-31: New article published in Földtani Közlöny (in Hungarian): Modern methods of cyclostratigraphy and astrochronology and their applications. Cyclostratigraphy, the science of reading the stratigraphic record of Milankovitch cycles, i.e., climate cycles driven by periodic changes in Earth’s orbital parameters, both provides a means to measure geological time and to reconstruct palaeoclimate. Here, we review the physical drivers of cyclical changes in geological time series, introduce the steps of spectral analyses, and discuss case studies. Read the open access article here (in Hungarian). Ingyenesen olvasható magyarul itt.

2020-08-10: New article published in Nature Communications: Dual clumped isotope thermometry resolves kinetic biases in carbonate formation temperatures. Palaeotemperature reconstructions suffer from inaccuracies related to kinetic fractionations occurring during carbonate mineral growth. Here we show that dual clumped isotope thermometry can identify the origin of these kinetic biases and allows the reconstruction of accurate environmental temperatures. Read the open access article here. Read the press release in English here. Lies die Pressemitteilung auf Deutsch hier.